Electric terminal connector



Oct. 28, 1952 F. s. LAMB ELECTRIC TERMINAL CONNECTOR Filed Feb. 1, l 950lnven kovz Fredrick 5. Lamb, b [flame/444%.,

Hi5 A b bovheg.

Patented Oct. 28, 1952 Fredrick S. Lamb, Cleveland Heights, Ohio, assigner-to';General Electric Company, a co'rpo ration of New- YorkApplication February 1, 1950, Serial No. 141,783

My invention relates to electrical connectors of the plug typehavingprotrudingcontact prongs which are adapted to be inserted into'thecont act openings of an electrical seeker or 'recepf tacle. Suchplug-type connectors may be used, for example, as a base for electriclamps "or similar devices particularly of the low current type, or as anattachment plug for electric 'cords';

"It isan object *ofymy invention to provide a prong-type electricterminal connector of simple and relatively inexpensive construction andwhich may be easily and quickly assembled and connected to thecurrentsupply wiresof the electric lamp, cord, or other device to whichit is"attached.

Another object of my invention is to provide an electric terminalconnector or plug of the above type'havin'g mechanical, i. e.,solderless', electri cal connections of goodelectricalpropertiesfibetween the connector prongs and 'the-c'urrent'supply wires of the device to which the connector'is attached.

In accordance with the invention, an electric terminal'connector such asa lampbase" or electric cord plug is provided with"projcting con tactprongs or blades each formedof 'a strip of suitable material, such asbrass,which is secured to'an insulative -wall portion'of the plug orbase body within an opening thereina'nd which ex tends outwardly fromthe wall and'is bentbackupon itself to' form two separated side-by-sideleg portions between which the "current cohduc tor extends, one of theprong legshav'ing a'guide ear pressed outward therefromto' provide apassageway through the prong leg serving to receive and guide thecurrent conductor intothe space between the prong legs upon itsbeingthreaded through the opening in the insulativewall, 1 the guide earbeing pinched against'thecurrent conductor to electrically connect thelatter to the Further objects and advantages of my invention will appearfrom the following detailed description of a species thereof andfrom theac-' companying drawing in which: Fig. 1 is a sectional view, on anenlarged scale, of. an electric incandescent lamp provided with a.terminal connector or base according to "the invention; Fig.2 is anexploded view of the base shown in Fig. 1 prior toassembly of the partsthereof, with the base shell shown partly broken" away; Fig.3 is aperspective view, partly broken away, of the base according to theinvention; and- Fig. 4 is'a fragmentary 9 can; (01. 173-361l While theinvention is shown in the drawings as employed in a base for an electricincandes cent lamp, it will be obvious that it maybe applied as well tobases for electric glow lamps or other discharge devices, or to aterminal connector or' attachment plug'cap for electric cords and thelike.

' Referring to the drawing, the lamp there shown comprises ahermetically'sealed glass envelope'or bulb l having a reentrant stem 2provided with a press 01' seal portione throughwhich are sealed a pairof lead-inor current supply conductorso'r wires 1!, 4. Disposed withinthe bulb I is a light source comprising a tungstenfilament 5electrically connected at its ends-to the lead-in wires 4 and supportedin position within the bulb by a plurality of support wires-6 anchoredin -a glass arbor 1 extending inwardly of the bulb from the stem press3'. The bulb-'1 is exhausted and, if desired, filled with a suitable gasthrough an exhaust tube 8 commum'cating with the interior of the bulb,which tube is afterwards-sealed or tipped-off, 'asindicated 7 at 9," tohermetically seal the bulb.

Suitably secured to the neck end of the bulb l, as by basingcement IDfor instan'cdfis an electric terminal connector or base i l" accordingto the invention and comprising a 'cupshap'ed body member 12' having acylindrical shell'po'r tion' l3 and an "insulative end' wall portion-14which may be made of any suitable insulating material such asglass,porcelain, molded pla'stic; or the'like. Projecting endwise from'the endwall l4 and securelyfastenedtheretois-apair of contact prongs IS, 15- towhichthe 'le'ad in' wires 4 are connected;

In accordance; with the invention, the said contact prongs or blades Hiareformed of-relatively stiff or rigid metal strip of suitablefcharactersuch as, for example, spring brass or bronze, and having a thickness ofthe orderof .025 inch and a width of around 4 inch or-so. "As shown inFig. 2,"the 'metal strip forming each prong' I5 is bent back uponitselfto form'two side side and slightly diverging leg portions?! l1 joined bya bent 'outer'end or bightportion l8. The-prongs l5 are securelyfastened in place on the base end wall [4; with their' ben'tor''bi'ghtends l8 outward and with one leg portion'fiziedly secured againsttransverse movement and-*th e other leg portion ffee to 'be movedtransversely For this purpose', one leg I6 is made longer-than theother'le'g I] and formed withan inner end portion I 9 which "is ofreduced width to form abutment shoulder '20'- at each side of the strip.

The said inner end portion 19 is also longitudinally slotted inward fromthe end thereof, as indicated at 2|, to form three locking tongues ortabs 22, 23, and 24, the center one 24 of which is preferably ofslightly greater width than the outer tongues 22, 23. The slotted ends19 of the prong legs l6 fit snugly within respective slots or openings25 in the insulative wall hi which slots, as shown, preferably extendparallel to one another so as to orient the prongs in the said wall withtheir flat sides parallel. Also, as shown, the two prongs l arepreferably positioned in the slots 25 with their shorter or bent legportions I I facing each other.

The narrowed end portion [9 of each prong leg i6 is of a length suchthat when it is inserted into the slot 25 with the shoulders 28 thereonbutt-ed up against the outer side 26 of the wall l4, the tongues 22, 23,and 24 will project inwardly beyond the inner side 21 of the said wall.The prong legs iii are secured or staked in place within the slots 25 bybending the inwardly projecting tongues 22, 23, and 24 over the innerside 21 of the wall It with the shoulders abutted against the outer side26 of the wall, the two outer tongues 22 and 23 preferably being bent inone direction and the center tongue 24 being bent in the oppositedirection, as shown. The prong legs l6 are thus fixedly anchored in theinsulative wall :4 against transverse movement. The other prong legs H,however, terminate just short of the outer side 26 of the wall i4 so asto be: freely movable transversely toward the anchored legs 16.

For making the connection of the lead-in wires 4 to the contact prongsIS, the slots in the wall l4 are each provided with a recess orenlargement 28 in one of their side walls through which recesses thelead-in wires 4 extend to the exterior of the base. As shown, therecesses 23 are preferably formed in the distal side walls of the twoslots 25. The said lead-in wire recesses or passageways 28 are flaredout toward the inner side 21 of the wall I4, as indicated at 29, inorder to facilitate insertion or threading of the lead-in wires 4therethrough during the assembly of the base I l onto the bulb l Thelead-in wires 4 extend through respective passageways or apertures 28 tothe exterior of the base wall 4 Where they are fastened to theassociated contact prongs iii to provide the electrical connectiontherebetween. For this purpose, the fixedly anchored leg l6 of eachprong is formed, immediately outward of the base wall [4, with apocket-like lug or ear 3B pressed outwardly from the metal strip toprovide a passageway 3! therethrough which faces and is directlyopposite the lead-in wire aperture or passageway 28 in the base wall l4so as to receive and guide the lead-in wire 4 into the space between theprong legs [6, l1 upon being threaded through the said wall aperture 28from the inside of the base. The portion of. the lead-in wire 4 whichextends through the passageway 3| formed by the pressed-out ear 39 ispinched between the rim 32 of the ear and that portion 33 of the prongleg l6 immediately inward of the ear 8i? (i. e., that portion of theprong leg bordering the shear cut of the lug rim 32) to thereby securelyfasten and electrically connect the wire to the prong. The pinching ofthe wires 4 to the prongs l5 may be efiected simply by positioning eachcontact prong between the jaws of a suitable pinching tool or pliers andclosing the jaws to apply pressure to the prong legs [8, ll at theregion of the ear 30, as indicated by the arrows in Fig. 1, so as tosqueeze the car 30 against the lead-in wire 4 and pinch it in place.

To facilitate threading of the lead-in wire through the ear passageway3|, and to aid in preventing the cutting or severing of the lead-inwire, during the pinching thereof, by the sheared edges of the prongpassageway 3|, which edges are apt to have sharp burrs thereon as aconsequence of the pressing out operation by which the ears or lugs 30are formed, the portion 33- of the prong leg 16 immediately inward ofthe lug or ear 38 is pressed slightly inward, i. e., in a directionopposite to the direction in which the ear 30 is pressed from the prongleg, to form a bent tongue as shown in Fig. 1. Such bending of the metalinward at 33 tends to prevent the subsequent pinching of the lead-inwire 4 so tightly as to cause the cutting thereof and, in addition,results in the formation of a larger and better-shaped passageway 3|which permits easier insertion and threading therethrough of the lead-inwires 4. To assure a positive and secure pinching of the lead-in wire 4between the ear 30 and the bent tongue 33, the free or spring leg I! ofthe prong should extend inwardly beyond the ear 3!! and thewire-pinching edge of the tongue 33 so as to engage the tongue and closeit against the lead-in wire when the prong legs are squeezed between thejaws of the pinching tool.

From the above, it will be evident that the base according to theinvention is of simple and relatively inexpensive construction and canbe assembled and the electrical connections made to the contact prongsthereof in a simple, easy and quick manner, without the need of anysoldering operations whatsoever. When plugged into a cooperating socket,the movable prong legs H, by virtue of their being in the nature ofspring arms, are pressed by the socket contacts toward the fixed pronglegs l6 thus squeezing the portion of the conductors 4 therebetween andfurther assuring a good electrical connection between the conductcrs andthe prongs. As shown, the prong legs 16, ll may be provided withcircular apertures or holes 34 adjacent their outer ends for the purposeof accommodating therein" normally present on the spring contacts ofconventional type sockets or receptacles into which the base or terminalconnector according to the invention is adapted to be plugged.

Although a preferred embodiment of my invention has been disclosed, itwill be understood that the invention is not to be limited to thespecific construction and arrangement of the parts shown but that theymay be widely modified within the spirit and scope of my invention asdefined by the appended claims.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. An electrical connector comprising a body member provided with aone-piece insulative wall portion having an opening therethrough, and acontact prong comprising a strip of metal secured to the said wall andextending outwardly therefrom and bent back upon itself to form atwo-legged prong, said prong having portions thereof outwardly adjacentsaid wall spaced apart laterally of the prong to provide a spacetherebetween positioned directly opposite and opening toward the saidwall opening so as to receive a current conductor upon its beinginserted straight through the said wall opening from the inneriside ofsaid wall, said prong por tions being relatively deformable to pinch thesaid conductor therebetween, one .of the legs of said prong beinganchored in said wall against transverse movement and the otherof saidlegs being transversely movable toward and coextensive with at least themajor portion of the protruding length of the anchored leg.

2. An electrical connector comprising a body member provided with aone-piece insulative wall portion having an opening therethrough, and acontact prong comprising a strip of metal secured to said wall Withinthe said opening thereand extending outwardly therefrom and bent backupon itself to form a two-legged prong, said prong" having portionsthereof outwardly-adjacent' said wall spaced apart laterally of theprong'to provide a space therebetween positioned directly opposite andopening toward the: said wallopeningso as to receive acurrent conductorupon its beinginserted straight through thesaid wall opening from theinner side of said wall, said prongportions being relatively deformablelaterally of the prong to pinch the said conductor therebetween, saidprong further having locking shoulders thereon engaging the inner andouter sides of said wall to longitudinally fix the prong in position onsaid wall, one of the legs of said prong being anchored insaid'. wallagainst transverse movement and the other of said legs being freelymovable transversely toward and coextensive with at least the majorportion of theprotruding length of the-anchoredleg.

3. An electrical connector comprising a body member provided with aninsulative wall portion having an opening therethrough, and a contactprong comprising a strip of metal secured to the said wall within thesaid opening and extending outwardly from the wall and bent back uponitself to form two separated and approximately SidQ-by-side legportions, one of said prong leg portions being anchored in said wallagainst transverse movement and being formed, outwardly adjacent saidwall, with a pocket-shaped ear pressed outwardly from said leg portionto one side thereof and closely adjacent said wall to provide apassageway therethrough facing and directly opposite the said wallopening and propositioned to receive a current conductor upon its beinginserted straight through said opening from the inner side of said wall,said ear being deformable relative to said leg portion to pinch theconductor therebetween, and the other of said prong leg portions beingtransversely movable towards the anchored leg portion and extending backalong the other side of the anchored leg portion a distance to at leastoverlap and conceal the exposed outer end of the said current conductorwhen inserted and clamped in place in said passageway.

4. An electrical connector comprising a body member provided with aninsulative wall portion having a slot therethrough formed with a recessin one side Wall thereof, and a contact prong comprising a strip ofmetal snugly fitting and securely locked within the said slot to firmlyanchor it to said wall and extending outwardly from the wall and bentback upon itself to the side away from the recessed side of said slot toform two separated and approximately side-by-side leg portions, theanchored leg portion of said prong being formed, outwardly adjacent saidwall, with a pocket-shaped ear pressed outwardly from said leg portionto the same side as the recessed side oiztheslot to provide. apassageway tlierethrough facing and directly oppositethe saidrecess the.slot and proportioned to receive a current conductor upon its beinglinserted straight through said recess from the inner side .ofsaid wall,said ear being deformable relative -.to said leg portion to pinch theconductortherebetween, and'thelother of said prong leg portions beingfreely movable transversely towards the anchored leg portion andextending back along the. antchored leg portion a distance to atleastloverlap and conceal the exposed outer. end ofthesaid currentconductor when inserted and clamped in place in said passageway.

5. An electrical connector comprisingabody member provided with aninsulative wall portion having an opening therethrough, and a contactprongcomprising a strip o'f-metal secured to the said wallwithin-thesaid opening and extending outwardly fromthe-wall and bentback upon itself toformtwo separated and approximatelyside-by-sideleg-portions, one of said prong'leg portionsbeing anchoredin said wall against transverse movement and being formed with an earpressed outwardly from said leg por tion to provide a passagewaytherethrough-facing and directly opposite the said wall opening forreceiving a current conductoruponitsbeing threaded through said opening,said anchored leg portion also having the metal'thereof immediatelyinward of said ear. pressed out in a direction opposite to said ear, theother of said prong leg portions extending inwardly beyond said ear butterminating short of saidwall so as to be freely movable transverselytowards the anchored leg portion.

6. An electrical device having a --terminal-connector comprising a bodymember provided with a one-piece insulative wall portion having anopening therethrough, a contactprong compris ing a strip of metalsecuredto the said wall within the said opening therein and extending outwardlytherefrom and bent back upon itself to form a two-legged prong, saidprong having portions thereof outwardly adjacent said wall spaced apartlaterally of the prong to provide a space therebetween positioneddirectly opposite and opening toward the said wall opening so as toreceive a current conductor upon its being inserted straight through thesaid wall opening from the inner side of said wall, and a currentconductor extending through said opening into the said space between thesaid prong portions and pinched therebetween, one of the legs of saidprong being anchored in said wall against transverse movement and theother of said legs being transversely movable toward and coextensivewith at least the main portion of the protruding length of the anchoredleg.

"7. An electric lamp comprising an envelope, an electric energytranslation element in said envelope, current conductors connected tosaid translation element and sealed through said envelope to theexterior thereof, and a base secured to said envelope and comprising aninsulative wall portion having a plurality of openings through which thesaid conductors extend, and a plurality of contact prongs eachcomprising a strip of metal secured to the said wall within respectiveones of said wall openings and extending outwardly from the wall andbent back upon itself to form a two-legged prong, each said prong havingportions thereof outwardly adjacent said wall spaced apart laterally ofthe prong to provide a space therebetween positioned directly oppositethe respective wall opening so as to receive a current conductor uponits being inserted straight through the said wall opening from the innerside of said wall, said current conductors extending into the said spacebetween and being pinched between the said portions of the respectiveprongs to electrically interconnect the same, one of the legs of eachprong being anchored in said wall against transverse movement and theother of said legs being transversely movable towards the anchored leg.

8. An electrical device having a terminal connector comprising a bodymember provided with an insulative wall portion having a plurality ofopenings therethrough, a plurality of contact prongs each comprising astrip of metal secured to the said wall within a respective one of saidwall openings and extending outwardly from the wall and bent back uponitself to form two separated and approximately side-by-side legportions, one of the leg portions of each prong being anchored in saidWall against transverse movement and being formed, outwardly adjacentsaid wall, with an ear pressed outwardly from said leg portion toprovide a passageway therethrough facing and directly opposite therespective wall opening, the other leg portion of each prong extendinginwardly beyond said ear and being freely movable transversely towardthe anchored leg portion, and a plurality of current conductorsextending through respective ones of said wall openings and through theear passageway in the associated prong and pinched between the said earand the body of the prong to electrically interconnect the conductors tothe respective prongs.

9. An electrical device comprising an envelope, an electric energytranslation element in said envelope, current conductors connected tosaid translation element and sealed through said envelope to theexterior thereof, and a base secured to said envelope and comprising aninsulative wall portion having a plurality of openings through which thesaid conductors extend, and a plurality of contact prongs eachcomprising a strip of metal secured to the said wall within a respectiveone of said wall openings and extending outwardly from the wall and bentback upon itself to form two separated and approximately side-by-sideleg portions, one of the leg portions of each prong being anchored insaid wall against transverse movement and being formed, outwardlyadjacent said wall, with an ear pressed outwardly from said leg portionto provide a passageway therethrough facing and directly opposite therespective wall opening, the other leg portion of each prong extendinginwardly beyond said ear and being freely movable transversely towardthe anchored leg portion, said current conductors extending through theear passageway in respective prongs and being pinched between the saidear and the body of the prong to electrically. interconnect theconductors to the respective prongs.

FREDRICK S. LAMB.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 822,469 Opitz June 5, 19061,521,197 Lewis Dec. 30, 1924 1,921,823 Hosking Aug. 8, 1933 2,049,152Biggs July 28, 1936 2,183,109 Sipe Dec. 12, 1939 2,383,263 Kruger Apr.21, 1945 2,420,754 McFadden May 20, 1947 FOREIGN PATENTS Number CountryDate 618,961 France Dec. 23, 1926 342,948 Great Britain Feb. 12, 1931

